Brazed or silver soldered.
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Screwed
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Welded
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Home made barrels for Marlin Model 90. Do not know which seems worse, the screw used to attach the hanger to the 20 barrel or the weld to the .410 barrels? Used Remington barrels for the 20 and Model 42 barrels for the .410. Funny thing is they tried to attribute the workmanship to Simmons. Simmons ought to sue.